Diaphragm for pressure-regulating valves.



No; 655,36l. Patented Aug. 7, I900.

} A. W. CASH. DIAPHRAGM FOB PRESSURE REGULATING VALVES.

(Application filed Oct. 5, 1899.)

No Model.)

172mm)? 0175M? W m UNITED STATES PATENT OEEI E,

ARTHUR \V. CASH, OF NEWARK, NEW JERSEY, ASSIGNOR TO THE FOSTER ENGINEERING COMPANY, OF SAME PLACE.

DIAPHRAGM FO'R PRESSURE-REGULATING VALVES.

SPECIFICATION forming part of Letters Patent No. 655,361, dated August 7, 1900.

Application filed October 5, 1899. Serial No. 732,663. (No model.)

To all whom it may concern: some thin tough metal without corrugations Be it known that I, ARTHUR W. CASH, a citiand bulged or dish-shaped sufficiently to allow zen of the United States, residing at Newark, of the required movement and provided with in the county of Essex and State of New J erradial slots, which do not, however, materi- 5 sey, have invented new and useful Improveally detract from its strength and yet permit ments in Diaphragms for Pressure-Regulatof the continued and prolonged movement of ing Valves, of which the following is a specithe diaphragm without cracking or breaking. fication. This slotted plate in itself cannot be com- This invention relates to an improved diaplete or sufiicient, as the radial slots would 1o phragm for pressure-regulating valves and permit escape of the fluid-pressure. To overother service-such as gages, recorders, &c.- come this difficulty, I provide an inner imperandhas foritsobjectto provideadiaphragm of forate diaphragm-plate made, preferably, of durable construction and having a proper desome very thin, tough, and non corrosive gree of flexibility to permit of the required metal, such as phosphor-bronze. This inner I 5 movements. diaphragm-plate is provided with annular cor- In that class of pressure reducing and regurugations which freely permit of its continued laiing valves where the valve proper is atand prolonged movement withoutbuckling or tached to and its movement controlled by a cracking, and being without any slots or other diaphragm which in turn receives its moveopenings it forms a seal through which the 2o ment by reason of the fluid-pressure acting fluid-pressure cannot pass. Thus the inner on its inner side, tending to close the valve, thin corrugated metal diaphragm-plate forms and springs or weighted levers acting against a seal capable of withstanding the action of its outer side, tending to open the valve, the water, steam, air, gas, &c., without any liadiaphragm must be of sufficient dimensions bility to deterioration of said inner plate,

25 to readily overcome the weight and friction while the outer non-corrugated diaphragmof the moving valve and yet be sufficiently plate composed of thicker stronger metal, fiexible and pliable to permit of the full openpreferably steel, and provided with the radial ing or movement of the valve without undue slots will give the required flexibility and the change in the reduced or regulated pressure. necessary strength to hold and sustain the 0 The common and well-known practice in this inner diaphragm-plate and the pressure actconnection has been to use diaphragms coning against it. structed of some thin tough metal and pro My invention therefore consists of a diavided with annular corrugations which give phragm for pressure-regulating devices comthe desired flexibility and permit of the re posed of an inner sheet or plate of thin metal 35 quired movement, but lacking the very essenhaving annular corrugations and an outer tial property of being able to withstand comsheet or plate of metal not corrugated, but paratively-high pressures without excessive slightly bulged or dish-shaped and provided stretching or bulging. Heretofore to avoid with radial slots, whereby the inner diaserious weakness a diaphragm made of a cirphragm-plate forms the seal and the outer o 40 cular sheet of thin tough metal without cordiaphragm-plate gives the strength to resist rugations and only slightly bulged or dishthe fluidpressure acting against the inner shaped has been used. A diaphragm of this plate, as hereinafter described and claimed. construction gives the desired strength to In the annexed drawings, illustrating my stand the high pressure, but soon becomes invention, Figure 1 is a sectional side eleva- 45 buckled or cracked, due to the continued extion of my improved diaphragm,'showing the cessive movement required to operate the lower or inner corrugated plate and an upper valve. or outer non-corrugated plate, together with To overcome the various objections to which the rims or flanges of the valve-casing between the diaphragms for pressure-reducing valves which the-two diaphragm-plates are clamped 1o 2 5c and like devices are subject, I have devised and held in position, also showing a central a diaphragm comprising a plate or sheet of upper or outer plate against which the springs or levers act and a portion of the inner part to which the valve proper is to be mechanically connected. Fig. 2 is a plan or top view of the upper or outer non-corrugated diaphragm-plate provided with radial slots. Fig. 3 is an under plan of the bottom or inner corrugated diaphragm-plate. Fig. 4 is a diagrammatic representation of the upper diaphragm-plate, in which the full lines represent about the central section of the non-corrugated plate when held at its full upward or outward movement by the fluid-pressu re, the dotted lines representing about the central section when the diaphragm is in a central position and the valve one-half open, the fluidpressure causing it to assume a curved position.

Referring to Fig. 1, the numerals 1 and 2 designate the flanged rim portions of the upper and lower parts of a valve-casing between which the diaphragm is securely clamped, as by means of bolts 3 at the edges of the diaphragm, as shown. The reference-numeral 4, Figs. 1, 2, and 4, designates the upper diaphragm-plate, which is preferably made of steel, though it may be constructed from some other thin tough metal. This upper diaphragm-plate 4 is bulged or dished, as shown, to a suflicient extent to allow for the required movement, and, as shown in Fig. 2, it is provided with a number of radial slots 5, which are extended from the centrally-clamped portion of the diaphragm to points near its periphery, and thereby add to the flexibility and pliability of this plate without materially impairing its strength. Beneath the upper diaphragm plate 4 and in close proximity therewith is placed the lower diaphragm-plate 6, which is preferably made of a thin tough metal, such as phosphor-bronze. This lower or inner diaphragm-plate 6 is provided with a suitable number of annular corrugations 7, Figs. 1 and 3, which impart the required flexibility and permit continued and prolonged movement or vibration of this plate without liability to buckling or cracking. This lower diaphragm-plate 6 being wholly imperforate forms a continuous seal through which the fluid-pressure cannot pass, and the construction of this plate is such that it is capable of withstanding the action of fluids and gases without injury or deterioration.

To the upper diaphragm-plate 4 there is secured a central upper plate or disk 8 to atford a bearing for the usual springs or weighted levers that act against the outer side of the diaphragm in a direction tending to open the valve. The'disk 8 may be secured in place by means of bolts and nuts 9, which also secure to the under side of the inner corrugated diaphragm 6 an inner disk or plate 10, that may have lugs or ears 11 thereon for connection of the diaphragm with the valve proper.

By reference to Fig. 1 it will be observed that the rims 1 and 2 and the disks 8 and 10 hold the two diaphragm-plates 4 and 6 in carried on the upper or 'outer diaphragmplate.

By making the upper non-corrugated and radially-slotted diaphragm-plate 4 from steel and constructing the lower corrugated plate (3 from phosphor-bronze and by arranging and connecting these plates in the manner described a most excellent result is obtained and at less cost than by using several corrugated or dished diaphragms, as heretofore.

The radially-slotted upper diaphragm-plate provides strength to withstand the pressure, and yet it is sufficiently flexible to permit a maximum movement without buckling or cracking, while the inner corrugated diaphragm-plate being imperforate forms a seal to prevent the escape of fluid-pressure and is also sufficiently flexible to follow the outer slotted diaphragm-plate, against which it lies. A' single corrugated diaphragm does not usually have sufficient strength in itself to withstand high pressures; but by combining such a plate with an upper radially-slotted plate of tough yet flexible and durable material there is produced a diaphragm that is -well suited to the requirements of pressurereducing valves and other devices for controlling fluid-pressure. A diaphragm of this construction is durable,extremely sensitive to variation of pressure, and is not liable to bucklin g or cracking or other injury in service.

In Reissue Patent No. 11,621 to John M. Foster, July 20, 1897, there is shown and claimed a flexible diaphragm composed of a number of non-corrugated plates, the upper ones having perforations to prevent high pressure from buckling or bulging the diaphragm in case of possible leakage of air past the lower diaphragm-plate. I am also aware that it has been proposed to strengthen either a corrugated or non-corrugated diaphragm-plate by means of radially-arranged segmental plates superposed on the lower diaphragm-plate; but my invention diifers from all others of which I am aware in combining with an inner or lower corrugated and imperforate diaphragm-plate an outer or upper flexible plate provided with radial slots, such slotted plate not only giving the diaphragm additional strength to resist any tendency to buckling, bulging, or cracking, but, furthermore, imparting the greatest possible flexibility to permit a maximum movement of the diaphragm with a perfectly-free action and without any liability to injurious strain.

My improved diaphragm composed of an imperforate and'corrugated thin metal plate and a non-corrugated radially-slotted plate secured together in contact with each other will permit of excessive and continual vibration without buckling or premature rupture. It is usual for plain diaphragm-plates to buckle or crack in radial directions. Hence IIO the advantage of providing such plates in a compound diaphragm with a plurality of radial slots that will counteract a tendency to buckling, bulging, or cracking. In the Foster diaphragm above referred to the nonradial perforations do not add to the life or lasting quality of the diaphragm as afiected by excessive or continued vibration or movement and do not lessen the tendency of the diaphragm to buckle and finally crack or break, such perforations being designed to accomplish the sole purpose of relieving any fluid-pressure that might otherwise accumulate between the plates composing the diaphragm by reason of a leak around the central stem or through any slight crack in the plate next to the fluid-pressure. While a corrugated diaphragm-plate has a flexibility similar to my radially-slotted diaphragmplate, it does not possess the strength of the latter. By combining these plates in a single diaphragmnamely,an inner flexible and imperforate plate of thin corrugated metal to be directly acted on by the fluid-pressure and an outer non-corrugated flexible plate provided with radial slots to brace the corrugated and imperforate inner plate, said plates being secured together in close juxtapositionI obtain at comparatively-small expense a diaphragm that possesses the required flexibility with strength to Withstand excessive or continued vibration, thereby practically obviating any tendency of the diaphragm to buckle and finally crack or break.

What I claim as my invention is- 1. The hereindescribed diaphragm for pressure-regulating devices, composed of an inner flexible sheet or plate of thin metal corrugated, and an outer flexible sheet or plate of metal non-corrugated but slightly bulged or dish-shaped and provided With a number of radial slots extended from a centrallyclamped portion of the diaphragm to points near its periphery, said plates being secured together in close juxtaposition, whereby the inner corrugated diaphragm-plate forms the seal and the outer radially-slotted diaphragmplate gives the strength and flexibility to resist the fluid-pressure acting against the inner plate and prevent buckling or cracking, substantially as specified.

2. The herein described diaphragm for pressure-regulating devices, composed'of an inner flexible sheet or plate of thin metal provided with annular corrugations,and an outer flexible sheet or plate of metal having a plurality of radial slots extended from a centrally-clamped portion of the diaphragm to points near its periphery, said plates being secured together in close j uxtapositiomwhere by the inner corrugated diaphragm-plate forms the seal and the outer radially-slotted diaphragm-plate imparts the required flexibility and strength to resist fluid-pressure acting against the inner plate and prevent buckling, cracking and strain, substantially as specified.

In testimony whereof I have hereunto set my hand in presence of two subscribing Witnesses.

ARTHUR W. CASH. Witnesses:

JOHN W. MILLER, FREDERICK J. GREENBERG. 

